Not getting the FPS i used to

Game now is running really bad, like really bad…
I’ve reinstalled and done everything ive seen in forums to make it run better but im still getting 100-144 fps but with tones of fps drops and lots of lag. used to get 250+ frames no problem. would like to get this fixed. Any help is much appreciated, thanks.

Have you followed any of the recommended steps here? GUIDE: Maximizing System Performance for Overwatch (PC)